Feshbach resonances and weakly bound molecular states of boson-boson and boson-fermion NaK pairs

We study theoretically magnetically induced Feshbach resonances and near-threshold bound states in isotopic NaK pairs. Our calculations accurately reproduce Feshbach spectroscopy data on Na$^{40}$K and explain the origin of the observed multiplets in the p-wave [Phys. Rev. A 85, 051602(R) (2012)]. We apply the model to predict scattering and bound state threshold properties of the boson-boson Na$^{39}$K and Na$^{41}$K systems. We find that the Na$^{39}$K isotopic pair presents broad magnetic Feshbach resonances and favorable ground-state features for producing non-reactive polar molecules by two-photon association. Broad s-wave resonances are also predicted for Na$^{41}$K collisions.Comment: 39 pages, 15 figures. Phys. Rev. A in pres

On Safety Assessment and Base Isolation of Heavy Non-structural Monolithic Objects

Abstract Under seismic actions heavy non-structural objects, which are usually placed at the top of existing constructions, may constitute a danger to human lives and a considerable loss for world heritage. In this contribution, safety assessment of non-structural monolithic objects is discussed through the illustration of a case study, which concerns seismic protection of eleven ancient marble decorative pinnacles placed at the top of a three-arched masonry city gate in Ferrara (ITALY). A method for assessing the safety of the underlying masonry structure under the action of seismic excitations is outlined and the amplification of the ground motions due to the presence of such structure is evaluated

Polar molecule reactive collisions in quasi-1D systems

We study polar molecule scattering in quasi-one-dimensional geometries. Elastic and reactive collision rates are computed as a function of collision energy and electric dipole moment for different confinement strengths. The numerical results are interpreted in terms of first order scattering and of adiabatic models. Universal dipolar scattering is also discussed. Our results are relevant to experiments where control of the collision dynamics through one dimensional confinement and an applied electric field is envisioned.Comment: 25 pages, 13 figure

Co-digestion of macroalgae for biogas production: an LCA-based environmental evaluation

Algae represent a favourable and potentially sustainable source of biomass for bioenergy-based industrial pathways in the future. The study, performed on a real pilot plant implemented in Augusta (Italy) within the frame of the BioWALK4Biofuels project, aims to figure out whether seaweed (macroalgae) cultivated in near-shore open ponds could be considered a beneficial aspect as a source of biomass for biogas production within the co-digestion with local agricultural biological waste. The LCA results confirm that the analysed A and B scenarios (namely the algae-based co-digestion scenario and agricultural mix feedstock scenario) present an environmental performance more favourable than that achieved with conventional non-renewable-based technologies (specifically natural gas - Scenario C). Results show that the use of seaweed (Scenario A) represent a feasible solution in order to replace classical biomass used for biofuel production from a land-based feedstock. The improvement of the environmental performances is quantifiable on 10% respect to Scenario B, and 38 times higher than Scenario

Direct evaporative cooling of 39K atoms to Bose-Einstein condensation

We report the realization of Bose-Einstein condensates of 39K atoms without the aid of an additional atomic coolant. Our route to Bose-Einstein condensation comprises Sub Doppler laser cooling of large atomic clouds with more than 10^10 atoms and evaporative cooling in optical dipole traps where the collisional cross section can be increased using magnetic Feshbach resonances. Large condensates with almost 10^6 atoms can be produced in less than 15 seconds. Our achievements eliminate the need for sympathetic cooling with Rb atoms which was the usual route implemented till date due to the unfavourable collisional property of 39K. Our findings simplify the experimental set-up for producing Bose-Einstein condensates of 39K atoms with tunable interactions, which have a wide variety of promising applications including atom-interferometry to studies on the interplay of disorder and interactions in quantum gases.Comment: 7 pages, 6 figure

Il sistema giudiziario Ucraino al vaglio del consiglio d'Europa

La scelta di un sistema appropriato per procedere alle nomine giudiziarie1 costituisce uno delle principali difficoltà ai quali si scontrano le nuove democrazie, spesso preoccupazioni per l’indipendenza e l’imparzialità politica del potere giudiziario. I’intervento del potere politico nella procedura di nomina, compromette la neutralità della giustizia in questi stati, tant’è che in altri paesi, particolarmente in questi , dove il sistema giudiziario ha fatto da testimone del suo carattere democratico; tali metodi nomina sono considerati efficaci e. Le norme internazionali a riguardo sono piuttosto favorevoli alla depoliticizzazione generale; non esistono tuttavia dei modelli unici di nomina potendo, assicurare in maniera ideale, dei principi della separazione del potere e l’indipendenza del potere giudiziario

Accurate near-threshold model for ultracold KRb dimers from interisotope Feshbach spectroscopy

We investigate magnetic Feshbach resonances in two different ultracold K-Rb mixtures. Information on the K(39)-Rb(87) isotopic pair is combined with novel and pre-existing observations of resonance patterns for K(40)-Rb(87). Interisotope resonance spectroscopy improves significantly our near-threshold model for scattering and bound-state calculations. Our analysis determines the number of bound states in singlet/triplet potentials and establishes precisely near threshold parameters for all K-Rb pairs of interest for experiments with both atoms and molecules. In addition, the model verifies the validity of the Born-Oppenheimer approximation at the present level of accuracy.Comment: 9 pages, 7 figure